The present invention, in some embodiments thereof, relates to vascular modeling, and, more particularly, but not exclusively, to the use of a vascular model for producing indices relating to vascular function and diagnosis in real time—for example, during a catheterized imaging procedure.
Arterial stenosis is one of the most serious forms of arterial disease. In clinical practice, stenosis severity is estimated by using either simple geometrical parameter, such as determining the percent diameter of a stenosis, or by measuring hemodynamically based parameters, such as the pressure-based myocardial Fractional Flow Reserve (FFR). FFR is an invasive measurement of the functional significance of coronary stenoses. The FFR measurement technique involves insertion of a 0.014″ guidewire equipped with a miniature pressure transducer located across the arterial stenosis. It represents the ratio between the maximal blood flow in the area of stenosis and the maximal blood flow in the same territory without stenosis. Earlier studies showed that FFR<0.75 is an accurate predictor of ischemia and deferral of percutaneous coronary intervention for lesions with FFR≥0.75 appeared to be safe.
An FFR cut-off value of 0.8 is typically used in clinical practice to guide revascularization, supported by long-term outcome data. Typically, an FFR value in a range of 0.75-0.8 is considered a ‘grey zone’ having uncertain clinical significance.
Modeling vascular flow and assessing vascular flow is described, for example, in U.S. published patent application No. 2012/0059246 of Taylor, to a “Method And System For Patient-Specific Modeling Of Blood Flow”, which describes embodiments which include a system for determining cardiovascular information for a patient. The system may include at least one computer system configured to receive patient-specific data regarding a geometry of at least a portion of an anatomical structure of the patient. The portion of the anatomical structure may include at least a portion of the patient's aorta and at least a portion of a plurality of coronary arteries emanating from the portion of the aorta. The at least one computer system may also be configured to create a three-dimensional model representing the portion of the anatomical structure based on the patient-specific data, create a physics-based model relating to a blood flow characteristic within the portion of the anatomical structure, and determine a fractional flow reserve within the portion of the anatomical structure based on the three-dimensional model and the physics-based model.
Additional background art includes:
U.S. Published Patent Application No. 2012/053918 of Taylor;
U.S. Published Patent Application No. 2012/0072190 of Sharma et al.;
U.S. Published Patent Application No. 2012/0053921 of Taylor;
U.S. Published Patent Application No. 2010/0220917 of Steinberg et at;
U.S. Published Patent Application No. 2010/0160764 of Steinberg et al.;
U.S. Published Patent Application No. 2012/0072190 of Sharma et al.;
U.S. Published Patent Application No. 2012/0230565 of Steinberg et al.;
U.S. Published Patent Application No. 2012/0150048 of Kang et al.;
U.S. Published Patent Application No. 2013/0226003 of Edic at al.;
U.S. Published Patent Application No. 2013/0060133 of Kassab et al.;
U.S. Published Patent Application No. 2013/0324842 of Mittal et al.;
U.S. Published Patent Application No. 2012/0177275 of Suri and Jasjit;
U.S. Pat. No. 6,236,878 to Taylor et al.;
U.S. Pat. No. 8,311,750 to Taylor;
U.S. Pat. No. 7,657,299 to Hizenga et al.;
U.S. Pat. No. 8,090,164 to Bullitt et al.;
U.S. Pat. No. 8,554,490 to Tang et al.;
U.S. Pat. No. 7,738,626 to Weese et al.;
U.S. Pat. No. 8,548,778 to Hart et al.;
an article titled: “Determination of fractional flow reserve (FFR) based on scaling laws: a simulation study” by Jerry T. Wong and Sabee Molloi, published in Phys. Med. Biol. 53 (2008) 3995-4011;
an article titled: “A Scheme for Coherence-Enhancing Diffusion Filtering with Optimized Rotation Invariance”, by Weickert, published in Journal of Visual Communication and Image Representation; Volume 13, Issues 1-2, March 2002, Pages 103-118 (2002);
a thesis in a book titled “Anisotropic Diffusion in Image Processing”, by J. Weickert, published by B. G. Teubner (Stuttgart) in 1998;
an article titled: “Multiscale vessel enhancement filtering”, by A. F Frangi, W. J. Niessen, K. L. Vincken, M. A. Viergever, published in Medical Image Computing and Computer-Assisted Intervention-MICCA'98;
an article titled: “Determination of fractional flow reserve (FFR) based on scaling laws: a simulation study”, by Jerry T Wong and Sabee Molloi, published in Phys. Med. Biol. 53 (2008) 3995-4011;
an article titled: “Quantification of Fractional Flow Reserve Using Angiographic Image Data”, by S. Molloi, J. T. Wong, D. A. Chalyan, and H. Le, published in O. Dössel and W. C. Schlegel (Eds.): WC 2009, IFMBE Proceedings 25/II, pp. 901-904, 2009;
an article titled: “Quantification of fractional flow reserve based on angiographic image data”, by Jerry T. Wong, Huy Le, William M. Suh, David A. Chalyan, Toufan Mehraien, Morton J. Kern, Ghassan S. Kassab, and Sabee Molloi, published in Int J Cardiovasc Imaging (2012) 28:13-22;
an article titled: “An angiographic technique for coronary fractional flow reserve measurement: in vivo validation”, by Shigeho Takarada, Zhang Zhang and Sabee Molloi, published online on 31 Aug. 2012 in Int J Cardiovasc Imaging;
an article titled: “A new algorithm for deriving pulsatile blood flow waveforms tested using stimulated dynamic angiographic data”, by A. M. Seifalian, D. J. Hawkes, A. C. Colchester, and K. E. Hobbs, published in Neuroradiology, vol. 31, 263-269, 1989;
an article titled: “Validation of a quantitative radiographic technique to estimate pulsatile blood flow waveforms using digital subtraction angiographic data”, by A. M. Seifalian, D. J. Hawkes, C. R. Hardingham, A. C. Colchester, and J. F. Reidy, published in J. Biomed. Eng., vol. 13, no. 3, pp. 225-233, May 1991;
an article titled: “Validation of volume blood flow measurements using three dimensional distance-concentration functions derived from digital X-ray angiograms”, by D. J. Hawkes, A. M. Seifalian, A. C. Colchester, N. Iqbal, C. R. Hardingham, C. F. Bladin, and K. E. Hobbs, published in Invest. Radiol, vol. 29, no. 4, pp. 434-442, April 1994;
an article titled: “Blood flow measurements using 3D distance-concentration functions derived from digital X-ray angiograms”, by A. M. Seifalian, D. J. Hawkes, C. Bladin, A. C. E Colchester, and K. E. F. Hobbs, published in Cardiovascular Imaging, J. H. C. Reiber and E. E. van der Wall, Eds. Norwell, Mass., The Netherlands: Kluwer Academic, 1996, pp. 425-442;
an article titled: “Determination of instantaneous and average blood flow rates from digital angiograms of vessel phantoms using distance-density curves”, by K. R. Hoffmann, K. Doi, and L. E. Fencil, published in Invest. Radiol, vol. 26, no. 3, pp. 207212, March 1991;
an article titled: “Comparison of methods for instantaneous angiographic blood flow measurement”, by S. D. Shpilfoygel, R. Jahan, R. A. Close, G. R. Duckwiler, and D. J. Valentino, published in Med. Phys., vol. 26, no. 6, pp. 862-871, June 1999;
an article titled: “Quantitative angiographic blood flow measurement using pulsed intra-arterial injection”, by D. W. Holdsworth, M. Drangova, and A. Fenster, published in Med. Phys., vol. 26, no. 10, pp. 2168-2175, October 1999;
an article titled: “Dedicated bifurcation analysis: basic principles”, by Joan C. Tuinenburg, Gerhard Koning, Andrei Rares, Johannes P. Janssen, Alexandra J. Lansky, Johan H. C. Reiber, published in Int J Cardiovasc Imaging (2011) 27:167-174;
an article titled: “Quantitative Coronary Angiography in the Interventional Cardiology”, by Salvatore Davide Tomasello, Luca Costanzo and Alfredo Ruggero Galassi, published in Advances in the Diagnosis of Coronary Atherosclerosis;
an article titled: “New approaches for the assessment of vessel sizes in quantitative (cardio-)vascular X-ray analysis”, by Johannes P. Janssen, Andrei Rares, Joan C. Tuinenburg, Gerhard Koning, Alexandra J. Lansky, Johan I. C. Reiber, published in Int J Cardiovasc Imaging (2010) 26:259-271;
an article titled: “Coronary obstructions, morphology and physiologic significance Quantitative Coronary Arteriography” by Kirkeeide R L. ed. Reiber J H C and Serruys P W, published by The Netherlands: Kluwer, 1991, pp 229-244;
an article titled: “Coronary x-ray angiographic reconstruction and image orientation”, by Kevin Sprague, Maria Drangova, Glen Lehmann, Piotr Slomka, David Levin, Benjamin Chow and Robert deKemp, published in Med Phys, 2006 March; 33(3):707-718;
an article titled: “A New Method of Three-dimensional Coronary Artery Reconstruction From X-Ray Angiography: Validation Against a Virtual Phantom and Multislice Computed Tomography”, by Adamantios Andriotis, Ali Zifan, Manolis Gavaises, Panos Liatsis, Ioannis Pantos, Andreas Theodorakakos, Efstathios P. Efstathopoulos, and Demosthenes Katritsis, published in Catheter Cardiovasc Interv, 2008, Jan. 1; 71(1):28-43;
an article titled: “Noninvasive Measurement of Coronary Artery Blood Flow Using Combined Two-Dimensional and Doppler Echocardiography”, by Kenji Fusejima, MD, published in JACC Vol. 10, No. 5, November 1987: 1024-31;
an article titled: “New Noninvasive Method for Coronary Flow Reserve Assessment: Contrast-Enhanced Transthoracic Second Harmonic Echo Doppler”, by Carlo Caiati, Cristiana Montaldo, Norma Zedda, Alessandro Bina and Sabino Iliceto, published in Circulation, by the American Heart Association, 1999; 99:771-778;
an article titled: “Validation of noninvasive assessment of coronary flow velocity reserve in the right coronary artery-A comparison of transthoracic echocardiographic results with intracoronary Doppler flow wire measurements”, by Harald Lethena, Hans P Triesa, Stefan Kerstinga and Heinz Lambertza, published in European Heart Journal (2003) 24, 1567-1575;
an article titled: “Coronary flow: a new asset for the echo lab?” by Paolo Vocia, Francesco Pizzutoa and Francesco Romeob, published in European Heart Journal (2004) 25, 1867-1879;
an abstract titled: “Quantification of the effect of Percutaneous Coronary Angioplasty on a stenosed Right Coronary Artery” by Siogkas et al., published in Information Technology and Applications in Biomedicine (ITAB), 2010 10th IEEE International Conference on
a review paper titled: “Non-invasive assessment of coronary flow and coronary flow reserve by transthoracic Doppler echocardiography: a magic tool for the real world”, by Patrick Meimoun and Christophe Tribouilloy, published in European Journal of Echocardiography (2008) 9, 449-457; and
an article titled: “Detection, location, and severity assessment of left anterior descending coronary artery stenoses by means of contrast-enhanced transthoracic harmonic echo Doppler”, by Carlo Caiati, Norma Zedda, Mauro Cadeddu, Lijun Chen, Cristiana Montaldo, Sabino Iliceto, Mario Erminio Lepera and Stefano Favale, published in European Heart Journal (2009) 30, 1797-1806.
an abstract titled “Determining malignancy of brain tumors by analysis of vessel shape” by Bullitt et al., published in Medical Image Computing and Computer-Assisted Intervention-MICCAI 2004.
The disclosures of all references mentioned above and throughout the present specification, as well as the disclosures of all references mentioned in those references, are hereby incorporated herein by reference.